Collagenous colitis diagnosed after Clostridioides difficile infection in a 2‐year‐old girl.

The article focuses on a unique case of collagenous colitis (CC) in a pediatric patient following a Clostridioides difficile infection (CDI), marking the first reported instance of CC in a child in Japan. The 2-year-old girl, who had a history of egg white allergy and atopic dermatitis, initially presented with bloody diarrhea and was diagnosed with CDI. Despite treatment with oral vancomycin, her symptoms persisted, leading to a colonoscopy that revealed characteristics of CC, including lymphocyte-dominant inflammatory cell infiltration and a subepithelial collagen band. The case emphasizes the need for awareness of CC in children, as it is often underdiagnosed due to limited colonoscopy use in this population. Further research is suggested to better understand the pathophysiology of CC in pediatric patients. [Extracted from the article]